Seaworthy

Seaworthy is a test harness for Docker container images. It allows you to use Docker containers and other Docker resources as fixtures for tests written in Python.

Seaworthy supports Python 3.4 and newer. You can find more information in the documentation.

A demo repository is available with a set of Seaworthy tests for a simple Django application. Seaworthy is also introduced in our blog post on continuous integration with Docker on Travis CI.

For more background on the design and purpose of Seaworthy, see our PyConZA 2018 talk (slides).

Quick demo

First install Seaworthy along with pytest using pip:

pip install seaworthy[pytest]

Write some tests in a file, for example, test_echo_container.py:

from seaworthy.definitions import ContainerDefinition

container = ContainerDefinition(
    'echo', 'jmalloc/echo-server',
    wait_patterns=[r'Echo server listening on port 8080'],
    create_kwargs={'ports': {'8080': None}})
fixture = container.pytest_fixture('echo_container')


def test_echo(echo_container):
    r = echo_container.http_client().get('/foo')
    assert r.status_code == 200
    assert 'HTTP/1.1 GET /foo' in r.text

Run pytest:

pytest -v test_echo_container.py

Project status

Seaworthy should be considered alpha-level software. It is well-tested and works well for the first few things we have used it for, but we would like to use it for more of our Docker projects, which may require some parts of Seaworthy to evolve further. See the project issues for known issues/shortcomings.

The project was originally split out of the tests we wrote for our docker-django-bootstrap project. There are examples of Seaworthy in use there.